INFECTIONS Allergies, Fungal, Bacterial, Viral, Infection, Inflammation, and Genetic

Skin Homeostatic Imbalances Infections Skin can develop more than 1000 different ailments Most common skin disorders are allergies, bacterial, fungal, or viral infections Less common skin conditions are burns and skin cancer

Types of Infections Athlete’s foot – itchy, red, peeling condition between the toes from fungus. Boils and carbuncles Inflammation of the sebaceous glands by bacteria Area: hair follicles & sebaceous glands Cold Sores – also known as fever blisters – small fluid-filled blisters that itch and sting caused by herpes simplex virus – it can be activated by emotions, fever, or UV radiation – cold sores occur around the lips and in the oral mucosa of the mouth

Contact dermatitis – itching, redness, and swelling of the skin progressing to blisters – caused by exposure to chemicals that provoke allergic reactions Impetigo – pink, water-filled, raised lesions that develop a yellow crust and rupture – found around the mouth and nose – caused by bacterial infection – common in elementary school-aged children Psoriasis – chronic condition with reddened epidermal lesions covered with dry, silvery scales – can be disfiguring when severe – can be hereditary – attacks are triggered by trauma, infection, hormonal changes, and stress

Skin Cancer 2. Malignant Cancer – abnormal cell mass Two types of Cancer 1. Benign Does not spread (encapsulated) 2. Malignant Metastasized** (moves) to other parts of the body Skin cancer is the most common type of cancer Risk factors for skin cancer are exposure to UV radiation in sunlight

Skin Cancer Types 1. Basal cell carcinoma Least malignant Most common type Arises from stratum basale It is slow growing Full cure happens 99% of the cases where the lesion is removed surgically

Skin Cancer Types 2. Squamous cell carcinoma Arises from stratum spinosum Metastasizes to lymph nodes Lesion appear as a scaly reddened papule that forms a shallow ulcer with a raised border Appears often on the scalp, ears, dorsum of the hands, and lower lip Sun-induced Caught early and surgically removed or by radiation therapy, complete cure is good

Skin Cancer Types 3. Malignant melanoma Most deadly of skin cancers Cancer of melanocytes Can begin wherever there is pigment, most appear spontaneously, but some develop from pigmented moles Appears as a spreading brown to black patch and metastasizes rapidly to lymph and blood vessels Early detection helps survival using ABCD rule Treatment is surgical removal and chemotherapy

ABCD Rule A Asymmetry B Border Irregularity C Color D Diameter Two sides of pigmented mole do not match B Border Irregularity Borders of mole are not smooth C Color Different colors in pigmented area D Diameter Spot is larger then 6 mm in diameter

BURNS

Skin Homeostatic Imbalances Burns Tissue damage and cell death caused by heat, electricity, UV radiation, or chemicals Associated dangers 1. Dehydration 2. Electrolyte imbalance 3. Circulatory shock

Rule of Nines Way to determine the extent of burns Body is divided into 11 areas for quick estimation Each area represents about 9% Figure 4.11a

Severity of Burns First-degree burns Only epidermis is damaged Skin is red and swollen Heal in 2-3 days Example is sunburn Partial-thickness burn

Second-degree burns Severity of Burns Epidermis and upper dermis are damaged Skin is red with blisters No permanent scars, regrowth happens Partial-thickness burns

Third-degree burns Severity of Burns Destroys entire skin layer Burn is gray-white or black Nerve endings are burned, the area is not painful Regrowth cannot occur, skin grafting must be done to cover the exposed tissue Full-thickness burns

Critical Burns Burns are considered critical if: Over 25% of body has second degree burns Over 10% of the body has third degree burns There are third degree burns of the face, hands, or feet Joint injuries can be troublesome because scar tissue forms and can limit mobility